DIGITAL SIGNATURE GENERATOR, DIGITAL SIGNATURE VERIFIER, KEY GENERATOR, METHOD FOR GENERATING DIGITAL SIGNATURE, METHOD FOR VERIFYING DIGITAL SIGNATURE, METHOD FOR GENERATING KEY, DIGITAL SIGNATURE GENERATING PROGRAM, DIGITAL SIGNATURE VERIFYING PROGRAM, AND KEY GENERATING PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a digital signature system capable of generating a digital signature having high safety and reliability, based on a public key cipher obtainable with small computational complexity. SOLUTION: A digital signature generator has a storage means in which (x) coordinates and (y) coordinates in curved surfaces in a three-dimensional manifold A (x, y, s, t) defined on a finite field Fpdisplayed by the (x) coordinates, the (y) coordinates, a parameter (s), and a parameter (t), store sections D (ux(s, t), uy(s, y), s, t) displayed by functions of the parameters (s) and (t) as the finite field Fpand a privacy key for generating a signature. In the digital signature generator, the hash value of a message (m) is computed, the hash value is embedded in a 1 variable polynomial h(t), and a hash-value polynomial is generated. In the digital signature generator, the (x) coordinates and the (y) coordinates generate digital signatures Ds(Ux(t), Uy(t), t) as curves on a section displayed by the function of the parameter (t), by substituting the hash-value polynomial for the parameter (s) of the section stored in the storage means. COPYRIGHT: (C)2007,JPO&INPIT